Hydrogenic Transitions in Multiply Charged Fe and Ni Ions

Abstract

Ten lines in the range $3880\leqq \lambda \leqq 5666$ Å in the beam-foil spectrum of iron have been identified with specific hydrogenic transitions in Fe iv-viii. The same transitions were observed from Ni and Ar beams. Deviations from the hydrogenic wavelengths are shown to be consistent with that expected from core polarization. The absence of these lines in astrophysical sources is discussed. A wavelength table is presented for identification of hydrogenic transitions to be expected in beam-foil spectra.